I recently came into a striped down moped (labeled as SL700 Lion, its the same frame as the Capri 700 which can be found on Google). It has no wheels, battery, or motor, but the rest is there and the frame is in good shape, so I have started cleaning it up and getting ready to purchase a hub motor and batteries, but don't know exactly how much power I will need. The frame is fairly areodynamic as it is, and a few improvements can be made, its lightweight and small but not a toy either, so I'd like to get it up to about 40MPH (for driving arround town only), and with a distance of really no more than about 15 miles.
My question comes in at specifying the power rating of the hub motor and the capacity of the battery pack. I'm fairly sure that 48V is a good operating voltage to work with, and something around 20Ah or more should be a good amount of juice to work with. The original wheels were 10", and Kelley Controls LLC seems to make some nice motors that will fit into that spot, but at any appreciable currents it seems that the battery would be drained very quickly. My big concern is a lack of experience with how much power it takes to get up to speed in this frame and how much energy storage is needed to get a half worthwhile range. I've heard all kinds of claims about range and speed using an almost random grouping of motors and batteries with controllers that seem far to inefficient for what they need to do, and every dealer seems to think they know everything, so I'm coming here to humbly ask for help form people who have done this before.
As for the controller, which I haven't mentioned yet, I want to design and build my own BLDC motor controller, and I'd happily share the schematic and layout files with anyone interested.
Any recommendations on motors and batteries (I'm going with SLA for financial reasons) would be much appreciated!
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